Question

if cos t=0.8, then cos(2t)=?

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Answer 1

Answer:

hiiiiiii...............

Answer 2

$Given \: cos \:t = 0.8 \: --(1)$

$We \:know \: that ,$

$Cos \:2t \\= 2cos^{2} \:t - 1 \\= 2 \times (0.8)^{2} - 1 \: [ From \: (1) ]$

$= 2 \times 0.64 - 1$

$= 1.28 - 1$

$= 0.28$

Therefore.,

$\red{ Value \: of \: cos \:2t} \green { = 0.28}$

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